1. Field of the Invention
The invention relates in general to guide rails, and more specifically to new and improved guide rail clamping apparatus for attaching and accurately positioning elevator guide rails in a hatchway or hoistway of a building.
2. Description of the Prior Art
The movable elements of an elevator system, such as the elevator car and its counterweight, are guided throughout their respective travel paths in the hoistway of a building. The guiding system conventionally includes guide rails, which have a substantially T-shaped cross-sectional configuration, which rails are fixed in the hoistway, and guide elements, such as guide roller assemblies, with the guide elements being carried by the elevator car and counterweight. The guide elements coact with three guide surfaces on each of the guide rails to guide the movable elements.
When an elevator system is installed, extreme care must be taken to properly align the sections which make up each complete guide rail, to properly locate each group of aligned sections between the front and back walls of the hoistway, called the "fore-aft" axis, and to accurately space the two groups of aligned sections, called the "between guides" or B.G. axis.
The conventional T-shaped guide rail includes first and second flanges and a stem. The stem defines the three guide surfaces, one on the nose or face of the stem portion, and one on each side of the opposed surfaces of the stem.
My U.S. Pat. No. 4,431,087 discloses and claims a new and improved guide rail clamping assembly which facilitates making both the fore-aft and B.G. adjustments, all without releasing the rail clips from the guide rails. This clamping apparatus includes a first mounting member, also called a rail bracket, which is fixed to the building, a second mounting member, also referred to as an intermediate support member, first and second rail clip members, first and second bolts, and first and second nuts. The first and second bolts extend through openings in the first and second rail clip members, and threadably engage tapped openings in the second mounting member. The first and second bolts are tightened to firmly clamp the guide rail flanges between the second mounting member and the first and second rail clip members, which overlap the first and second flanges, respectively, of the guide rail. This forms a first or intermediate assembly which can be shimmed as a unit to the correct B.G. and "tapped" to the fore-aft plumb line.
The first and second bolts continue through elongated openings in the first mounting member, and the first and second nuts are loosely assembled on the bolts while the first assembly is being positioned. The nuts are then tightened on the first and second bolts, respectively, to firmly clamp the first assembly to the first mounting member, and thus to the associated building.